Congrats and welcome to the forum!
Yes, you can replace out the axleback exhaust, which will change the tone and sound more aggressive. Keep in mind, it will not sound like a V8.
I would highly recomment going to youtube and listen to different exhaust sets ups for your make/model car.
You can also check American Muscle for exhaust choices, prices and sound clips.
Scroll down to 2010-2013 Mustang V6 Axleback Exhaust section:
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